Connecting Refrigerant Pipes And Drain Pipes; Refrigerant Piping Work; Drain Piping Work; Connecting Electrical Connections - Mitsubishi Electric City Multi PWFY-P36NMU-E-BU Manuel D'installation

② If the unit is used on the highest story of a building and under conditions of
high temperature and humidity, it is necessary to use pipe size and insulating
8.1. Refrigerant pipe, drain pipe and lling port
[Fig. 8.1.1] (P. 5)
Ⓐ Refrigerant piping (gas)
Ⓒ Water inlet
Ⓔ Drain outlet

9. Connecting refrigerant pipes and drain pipes

9.1. Refrigerant piping work

both outdoor unit and BC controller (simultaneous cooling and heating series R2).
an outdoor unit is received by BC controller and branches at the BC control-
ler to connect between indoor units.
the outdoor unit manual.
Caution:
Install the refrigerant piping for the indoor unit in accordance with the
following.
1. Cut the tip of the indoor unit piping, remove the gas, and then remove the
brazed cap.
[Fig. 9.1.1] (P.5)
Ⓐ Cut here
Ⓑ Remove brazed cap
2. Pull out the thermal insulation on the site refrigerant piping, braze the unit
piping, and replace the insulation in its original position.
Wrap the piping with insulating tape.
Note:
Pay strict attention when wrapping the copper piping since wrapping
the piping may cause condensation instead of preventing it.
Before brazing the refrigerant piping, always wrap the piping on the main
*
body, and the thermal insulation piping, with damp cloths to prevent
heat shrinkage and burning the thermal insulation tubing
[Fig. 9.1.2] (P.5)
Ⓐ Thermal insulation
Ⓒ Wrap with damp cloth
Ⓔ Ensure that there is no gap here
Cautions On Refrigerant Piping
▶ Be sure to use non-oxidative bra ing for bra ing to ensure that no for-
eign matter or moisture enter into the pipe.
▶ Be sure to apply refrigerating machine oil over the flare connection
seating surface and tighten the connection using a double spanner.
▶ Provide a metal brace to support the refrigerant pipe so that no load is
imparted to the indoor unit end pipe. This metal brace should be pro-
vided 50 cm away from the indoor unit s are connection.
Warning:
When installing and moving the unit, do not charge it with refrigerant other
than the refrigerant (R407C or R22) speci ed on the unit.
- Mixing of a different refrigerant, air, etc. may cause the refrigerant cycle to mal-
function and result in severe damage.
Caution:
Use refrigerant piping made of C1220 (CU-D P) phosphorus deoxidi ed
copper as speci ed in the IS
less pipes and tubes". In addition, be sure that the inner and outer
surfaces of the pipes are clean and free of ha ardous sulphur, oxides,
dust/dirt, shaving particles, oils, moisture, or any other contaminant.
Never use existing refrigerant piping.
- The large amount of chlorine in conventional refrigerant and refrigerator oil
in the existing piping will cause the new refrigerant to deteriorate.
Store the piping to be used during installation indoors and keep both
ends of the piping sealed until just before bra ing.
- If dust, dirt, or water gets into the refrigerant cycle, the oil will deteriorate
and the compressor may fail.
12
Ⓑ Refrigerant piping (liquid)
Ⓓ Water outlet
*1: PWFY-P36/P72NMU-E2-AU
Ⓑ Pull out insulation
Ⓓ Return to original position
Ⓕ Wrap with insulating tape
3300 "Copper and copper alloy seam-
③

9.2. Drain piping work

1. Ensure that the drain piping is downward (pitch of more than 1/100) to the
outdoor (discharge) side. Do not provide any trap or irregularity on the way.
(①)
2. Ensure that any cross-wise drain piping is less than 20 m [65-9/16] (excluding
the difference of elevation). If the drain piping is long, provide metal braces
to prevent it from waving. Never provide any air vent pipe. Otherwise drain
may be ejected.
3. Use a hard vinyl chloride pipe VP-25 (with an external diameter of 32 mm [1-1/4])
for drain piping.
4. Ensure that collected pipes are 10 cm [5/16] lower than the unit body's drain
port as shown in ② .
5. Do not provide any odor trap at the drain discharge port.
6. Put the end of the drain piping in a position where no odor is generated.
7. Do not put the end of the drain piping in any drain where ionic gases are
generated.
[Fig. 9.2.1] (P. 5)
Ⓐ Downward slope 1/100 or more
Ⓑ Drain hose
Ⓒ Unit
Ⓓ Collective piping
Ⓔ Maximize this length to approx. 10 cm [5/16]

9.3. Connecting electrical connections

Verify that the model name on the operating instructions on the cover of the con-
trol box is the same as the model name on the nameplate.
Step 1
Remove the screws holding the terminal box cover in place.
[Fig. 9.3.1] (P. 5)
Ⓐ Screws
Ⓒ Control box
Note:
Ensure that the wiring is not pinched when tting the terminal box cover.
Pinching the wiring may cut it.
Caution:
Install wiring so that it is not tight and under tension. Wiring under tension
may break, or overheat and burn.
nections, and attach the cover onto the control box in the reverse order re-
moval.
[Fig. 9.3.2] (P. 5)
Ⓐ To prevent external tensile force from applying to the wiring connection section
Ⓑ External signal input cable
Ⓒ External signal output cable
Ⓓ Power source wiring
Ⓔ Tensile force
Ⓕ Use ordinary bushing
Ⓖ Transmission cable and MA remote controller cable
Ⓗ Conduit
Ⓘ Side frame
Ⓙ
Ⓚ Washer (accessory)
Caution:
Wire the power supply so that no tension is imparted. Otherwise disconnection,
heating or re result.
Ⓑ Front panel
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